College teams flip personnel all the time. Upperclassmen graduate or go pro, and prep players come in to restock the roster. Life goes on.

But only 11 starters will return to the Iowa football team next year. Riley Reiff and Marvin McNutt will wear NFL colors in the fall; there's a good chance Shaun Prater, Broderick Binns, and Mike Daniels will, too. Marcus Coker left in the wake of a team suspension, and the Des Moines Register reported on Monday night that he has transferred to play at Stony Brook (N.Y.) University.

The importance of replenishing the Hawkeyes can't be overstated, which is why it's good National Signing Day is slated for Wednesday. At least 22 players from 13 states had given oral commitments as of Monday night.

Those players will help coach Kirk Ferentz's team across all positions, but they will be especially vital to three depleted areas.

Running back

The second-leading rusher in the Big Ten is gone. So, too, is the player who was his best backup. So where does Iowa turn in the post-Coker and Mika'il McCall era?

Jordan Canzeri? He has talent, but his 5-9, 172-pound frame won't withstand the beatings that come with being a featured tailback in the Big Ten.

Brad Rogers? He played running back in high school, but he's developed into a good fullback, and it's hard to imagine him getting more than a few surprise touches per game.

Damon Bullock or De'Andre Johnson? They combined for 28 carries — a whopping 6 percent of Iowa's total and a sample size too small to give much more than an inkling of what each can do.

The Newcomers: Four-star Pennsylvanian Greg Garmon is the name most people recognize, and with good reason; he's big (6-2, 195 pounds), fast (4.4-second 40 time), and elusive. He'll be joined by incoming three-star Cedar Falls native Barkley Hill, who switched his commitment from Iowa State last week. Rivals.com reported that the Hawkeyes offered JuCo transfer Aaron Harris a scholarship, too; Harris ran for a cool 2,028 yards in two seasons at Southwestern (Calif.) Community College, and he has an official visit to Iowa City scheduled for Friday.

Wide receiver

The Hawkeyes only lose one receiver who pulled in a significant number of catches in 2011 — but Marvin McNutt was pretty damn good, and he is the outright holder of four major school receiving records.

The immediate load of pass-catching duties falls to Keenan Davis, who roped in 50 balls but suffered from a recurring case of the butterfingers. Kevonte Martin-Manley was great as Iowa's slot receiver — for a while, anyway. He made noise with 15 catches and 4 touchdowns in four nonconference games but didn't do much in the Big Ten (15 catches, no scores).

The Newcomers: At least three wideouts are expected to sign with Iowa on Wednesday, all of whom are three-star prospects. Greg Mabin, Cameron Wilson, and Tevaun Smith are all 6-2 and within four pounds of 190; Rivals.com called Wilson the No. 79 wide receiver in the country. Mabin and Smith weren't ranked, but neither was McNutt (to be fair, he was a quarterback) or Derrell Johnson-Koulianos. Both had extremely productive careers catching passes for the Black and Gold.

Defense

No individual position is listed here because the entire defense needs help. Iowa lost three-quarters of the defensive line, its most senior linebacker, and half of the backfield — the majority of a unit that ranked in the bottom half of the Big Ten in each major defensive category, including an 11th-place finish against the pass.

In other words, there will be plenty of opportunities for fresh faces to step in sometime in the near future; maybe not this coming season, but it won't take long.

The Newcomers: Ferentz will ink at least 10 defensive players this week, including a pair of four-star defensive linemen from Illinois. Faith Ekakitie is a 6-2, 255-pound end from Lake Forest; Jaleel Johnson, a 6-2, 277-pound tackle out of Lombard, kept Iowa guessing until last week, when Scout.com reported he canceled a planned trip to Michigan State.